Electrode assembly for electrondischarge tubes



Feb. 15, 1949. P. w. sTursMAN 2,461,578

ELECTRODE ASSEMBLY FOR ELECTRON-jDISCHARG TUBES Filed June 1, 1945 kof Fig, 1.

Patented Feb. 15,V 19149;)

ELECTRODE ASSEMBLY FOR ELECTRON- K vDISCHARGE TUBES I Paul W. Stutsman; Needham, Mass., assigner to Raytheonl Manufacturing Company, Newton,V Mass.; a corporation of Delaware Applca'tim June 1 1945,seria1 No. 5497.056

o 7 Claims. (01250-1215) e e 1 The present invention relates to electrondischarge tubes. e

' :One of the objects of the present invention is to provide an electron discharge tube with means for protecting elementsofthe electrode assembly from arcing and electron bombardment.

Another object of the present invention is to protect elements of the electrode assembly from deposits resulting from the flashing of the getter. These and such other aims and objects vof the present invention as may hereinafter appear will be best understood from the'following description taken in connection with the accompanying drawing of one embodiment of the invention,

hereinv presented for illustrative purposes.l

iIn the drawing: 'n g Fig. 1 is a longitudinal section on line I-l {of Fig. 2. .lilg. 2 is a transverse section taken on line 2-7-2 The tube shown in the drawing illustratively consists of a high voltage rectifier tube comprising an hermetically sealed `envelope 2 containing an electrode assembly comprising a lament cathode 4, a grid 5 surrounding said cathode, and a cylindrical anode 8 (see Fig. 2) surrounding said grid. Said filament-ary cathode is welded at its upper end to one end of a spring Ill which is welded at its other end to a conducting rod I2 (see Fig. 2). Said conductor rod I2 is welded at its lower end to a conductor I6. Said lamentary cathode extends through corresponding openings in upper and lower spacing members 32 and 34, hereinafter more fully described, and is welded at its lower end to a conductor I4.

The grid 6 is wound around and supported by vtwo diametrically opposed conducting rods I8 and 20. one of which, the rod for example, is welded at its lower end to said conductor I4.- The cylindrical anode 8 is supported by two diametrically opposed conducting rods 22 and 24 extending longitudinally of and welded to said anode plate 8 on the outer side of the latter. The lower ends Aof said two rods 22 and 24 are connected to each other by a metal ribbon 26 welded to a conductor 28 (see Fig. 2). Said conductors I4, I6, and 28 are butt-welded to lead-in conductors sealed through the base 30 of the tube and projecting therefrom as exterior contact prongs. The upper and lower spacing members above referred to consist of insulating plates 32 and 34, preferably of mica, provided at their edges with resilient teeth 36 (see Fig. 2) that yieldingly engage the lateral wall of said envelopeand brace said spacing members laterally. Said plates 32 prisesv insulatingcaps 38 enclosing.the.exposed Y l erably of glass.V

nd 34 are. providewith suitably spaced per.

lforations-throughwhich are threadedfthe said conducting rod I2 for the cathode, said gridsupporting rods I8 and 20 (see Fig. ,2),` and the/anodesupportingrods 22 and 24. 1.

In accordancewith the present invention, the portions of saiclplate supporting rods 22- andm24 that project above and below-said: anode plate? and are thus exposedvto, `electron?borrrbarrnent are protected e from such bombardment by .f suit.-y able meansg-Said means herein illustrated. cornupper end porti-onsy of saidrodsand insulating sleeves 40 enclosing theexposed lQWerend por"- tions `o1 said rods. Saidw caps andsleeves `maybe made of any suitable insulating.inaterial;` prei- The loweredgesfsjald caps 33y may rest upon theiupper. edgeorl said2anode plate V8, vand the lower edges of said jsle eves4il may vresti upon suitablepins 4I projecting irornaid rods 22, 24 and weldedv or otherwise fastened thereon. The caps 38 and sleeves 40 alsoreduce the probability of arcing between said rods and said cathode or other parts 0f the assembly `or at the junctions of conducting and non-conducting parts, such as said insulating plates 32 and 34, and along leakage paths. Said caps also protect said rods 32 and 24 from the deposit thereon of condensation products freed b-y the flashing of the getter. The latter is shown at 42 and is carried by a conductor 44 welded to an ear 46 projecting from the upper edge of a conducting shield 48 through said 'upper' spacing plate 32. Said shield comprises a metal cylinder surrounding the electrode -assembly and provided'upon the lower edge with ears 56 projecting through perforations in the lower spacing plate 34 and welded respectively to two bent conductors, only one of which is shown at 52. Said two bent conductors 52 are butt-welded to lead-in conductors 54 and 56, respectively, (see Figs. l and 2) sealed through said tube base 3G and projecting therefrom as exterior contact prongs. The conductors 52 support saidv shield at diametrically opposed points, and they also support said spacing plates 32 and 34 and the electrode assembly. `Said L shield completely surrounds the electrode assemto be considered in al1 respects as illustrative and not restrictive, reference being had to the appended claims, rather than to the aforesaid description, to indicate the scope of the invention.

What is claimed is:

`1. An electrode assembly comprising an insulatingrflectrode 4spacing member, an insulating sleeve "inserted 'through a perforation in -said spacing member, an electrode supporting rod having a portion thereof surrounded by said insulating sleeve, and means carriedby saidelectrode supporting rod for supporting saidinsulating sleeve. Y

2. An electrode assembly comprising van insulating electrode spacing member, an insulating sleeve inserted through a perforation in said spacing member, and an electrode. supporting rod having an end portion inserted in said sleeve, said sleeve being closed over` the end of said'electrode supporting rod inserted therein.

3. Anelectron-discharge tube comprising a iilamentarynatho'da anfanode 'surrounding said cathode, insulatingfele'ctrode spacing members, insulating sleeves inserted through said spacing members, anode supporting rods having portions thereof ysur-'rounded by said sleeves, 'and means carried' bysaid anode supporting rods` for-supporting said sleeves.

V4. An electron-discharge'tube comprising a 1:11-,

.'ament'ary cathode, -ananode surrounding said cathode, insulating electrode 'spacing members, a'n'ode supporting rods having their end portions threaded through said spacing members, glass sleeves surroundingV said end portions of said rods, I

and means 'carried by said rods yfor supporting saidl glass sleeves.

5. An electron-discharge tube comprising a, filvaimentary cathode, an anode surrounding said .cathode throughout a. portion of the length of said cathode, insulating `electrode spacing members, anode supporting rods having portions projecting beyond the ends of said anode and threaded through said spacing members, and insulating means surrounding said portions of said rods that project beyond the ends of said anode.

6. An electron-discharge tube comprising a cathode, ananode surrounding a portion of said d`cathode, yinsulating electrode spacing "members,

anode supporting rods having portions projecting beyond the ends of said anode and threaded through said spacing members, and insulating .means surrounding said portions of said rods that project beyond the ends of said anode.

Y 7. An electron-discharge tube comprising a Vdlamentary cathode, an anode surrounding said cathode throughout a portion of the length of said rcathode, ,insulating electrode spacing members, anode supporting rods having portions projecting'beyond the endsof said anode and threaded through said spacing members, and insulating means surrounding said portions ofsaid rods projecting beyond the ends of said anode, saidinsulating'means completely enclosing said portionsior said -rods that are threaded through one of said spacing members. v l

PAUL W.' STUTSMAN.

REFERENCES CITED The following references are .of recordinfthe 

